The transmural potential difference, short-circuit current, and Na fluxes have been investigated in an in vitro preparation of isolated rabbit ileum. When the tissue is perfused with a physiological buffer, the serosal surface is electrically positive with respect to the mucosal surface and the initial potential difference in the presence of glucose averages 9 mv. Unidirectional and net Na fluxes have been determined under a variety of conditions, and in each instance, most if not all of the simultaneously measured short-circuit current could be attributed to the active transport of Na from mucosa to serosa. Active Na transport is dependent upon the presence of intact aerobic metabolic pathways and is inhibited by low concentrations of ouabain in the serosal medium. A method is described for determining whether a unidirectional ionic flux is the result of passive diffusion alone, in the presence of active transport of that ion in the opposite direction. Using this method we have demonstrated that the serosa-to-mucosa flux of Na may be attributed to passive diffusion with no evidence for the presence of carrier-mediated exchange diffusion or the influence of solvent-drag.
Article|
January 01 1964
Ion Transport in Isolated Rabbit Ileum : I. Short-circuit current and Na fluxes
Stanley G. Schultz,
Stanley G. Schultz
From the Bionucleonics Department, School of Aerospace Medicine, Brooks Air Force Base Texas
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Ralph Zalusky
Ralph Zalusky
From the Bionucleonics Department, School of Aerospace Medicine, Brooks Air Force Base Texas
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Stanley G. Schultz
From the Bionucleonics Department, School of Aerospace Medicine, Brooks Air Force Base Texas
Ralph Zalusky
From the Bionucleonics Department, School of Aerospace Medicine, Brooks Air Force Base Texas
Received:
August 21 1963
Online ISSN: 1540-7748
Print ISSN: 0022-1295
Copyright ©, 1964, by The Rockefeller Institute Press
1964
J Gen Physiol (1964) 47 (3): 567–584.
Article history
Received:
August 21 1963
Citation
Stanley G. Schultz, Ralph Zalusky; Ion Transport in Isolated Rabbit Ileum : I. Short-circuit current and Na fluxes . J Gen Physiol 1 January 1964; 47 (3): 567–584. doi: https://doi.org/10.1085/jgp.47.3.567
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